Genetics

Learn Genetics University Utah

Centre for Genetics Education NSW au

http://www.youtube.com/watch?v=ra46BHYwjHs

http://www.youtube.com/watch?v=eOvMNOMRRm8

http://www.youtube.com/watch?v=7QwTEKhVEDk

http://www.youtube.com/watch?v=5x_Rp1mwotQ

 

Chromosome disorders and gene abnormalities
Translocations Downs
Turners
Klinefelters
Single Gene AD Adult PKCD
Neurofibromatosis
Huntingtons’ Chorea
Familial Hypercholesterolaemias
Marfans
Single Gene Disorders AR Cystic Fibrosis
Haemoglobinopathies
Haematochromatosis
Single gene X-linked Duchenne Muscular Dystrophy
Becker
Fragile X

 

Inherited Disease
AD
AR
X linked recessive
X linked dominant

 

Trisomies
Trisomy 21 Down’s
Trisomy 18 Edward’s
Trisomy 13 Patau’s
XXX Triple X syndrome
XXY Klinefelters
XYY XYY syndrome

 

Chromosome mutations
abnormal chromosome numbers
abnormal chromosome structures

http://www.youtube.com/watch?v=ab_B0lZqq6M

http://youtu.be/J1XQKI5s3Mc

http://youtu.be/mQhrhJn8chM

marfan association.org.uk

Bernard J.A. Marfan in 1896.
Connective tissue disease affecting skeleton, eyes, heart, lungs and blood vessels.
Caused by a mutation in the gene for fibrillin 1 on chromosome 15.
75% of cases are inherited, 25%  spontaneous mutation.
Each child of an affected parent has a 50% chance of inheriting MFS.
Affects both men and women of any ethnic group.
10,000 patients in UK (incidence approx. 1 in 5,000)

Marfans
Skeletal Tall thin physique, disproportionately long limbs, fingers and toes, lax
ankles, flat feet, spinal curvature, abnormally shaped narrow chest (with pigeon or funnel deformity), armspan usually greater than height, joint hypermobility or contractures and dislocations, striae. Dilatation of the lumbar dural sac (75% of patients). Hernias are common.
Cardiovascular Dilatation of ascending and sometimes descending aorta, incompetence of aortic and mitral valves, aneurysm and dissection of aorta.
Respiratory Pneumothorax bronchiectasis
emphysema and asthma
Ocular Lens subluxation /dislocation, myopia and unstable refraction, detachment of retinal detatchment, squint, glaucoma
Dental High-arched palate, crowding of teeth.

 

Achondroplasia (AD)

www.achondroplasia.co.uk

AD.
Small stature with shortened limbs with normal trunk length.
Apparent prominence of skull with prominent forehead and saddle nose.
Kyphosis. Small hands with fingers of equal length.

http://www.youtube.com/watch?v=0ra3_w28FkI&feature=related

 

Cystic Fibrosis (AD)

250textbooks/cystic-fibrosis

Cystic Fibrosis Trust UK

http://www.youtube.com/watch?v=6v5o9AzjH6Q

http://www.youtube.com/watch?v=HUCzNRdT8EI&feature=related

http://www.youtube.com/watch?v=FMAOEOmLoUE&feature=related

http://www.youtube.com/watch?v=WuI72eMrIQI&feature=related

 

Sickle cell  genetics

Sickle Cell Disease Association of America

NHS Sickle Cell and Thalassaemia Screening

http://youtu.be/R4-c3hUhhyc

http://youtu.be/RN2MKOx9wZU

http://youtu.be/x96ODlFiaEo

http://youtu.be/HWMcVtftunM

http://youtu.be/sAJMHpjARYI

http://youtu.be/uZ9uXsOPB2s

http://youtu.be/9UpwV1tdxcs

http://youtu.be/-xBvFd2dW4A

 

Thalassaemia genetics

alpha thalassaemia

beta thalassaemia

sickle cell disease

UK Thalassaemia Society

Thalassaemia @ LabtestsOnline

http://www.youtube.com/watch?v=Zp43iQOOiHg&feature=related

http://youtu.be/185ELUbYvxo

http://youtu.be/AYCHiYW9Des

1 gene affected  2 genes affected alpha thalassaemia traitmay be symptoms of mild anaemia.
If two people with the alpha thalassaemia trait have a child, there is a one-in-four chance that their child will inherit the most severe form of alpha thalassaemia3 genes affected Haemoglobin H disease.H disease will have lifelong (chronic) anaemia, and may require regular blood transfusionsAll four genes affectedalpha thalassaemia major. Infants with this condition are unable to produce normal haemoglobin and are unlikely to survive pregnancy. There have been some cases of unborn babies being treated with blood transfusions while still in the womb, but this type of treatment has a low success rate.

alpha thalassaemia
1 gene affected
2 genes affected alpha thalassaemia trait may be symptoms of mild anaemia.
If two people with the alpha thalassaemia trait have a child, there is a one-in-four chance that their child will inherit the most severe form of alpha thalassaemia
3 genes affected Haemoglobin H disease. H disease will have lifelong (chronic) anaemia, and may require regular blood transfusions
All four genes affected alpha thalassaemia major Infants with this condition are unable to produce normal haemoglobin and are unlikely to survive pregnancy. There have been some cases of unborn babies being treated with blood transfusions while still in the womb, but this type of treatment has a low success rate.

 

Inherited haemochromatosis

hemochromatosis.org

haemochromatosis @ Labtests online

Hereditary Haemochromatosis @ geneticseducaton.nhs.uk

Hereditary haemochromatosis Clinical review BMJ 2011;342:c7251

http://youtu.be/UeRr-S2aWrY

http://youtu.be/-E_kpdGcX-s

Laurence Moon Biedl Syndrome

AD. dwarfism obesity polydactyly or syndactyly genital hypoplasia and poorly developed secondary sexual characteristics. Mental defeciency, retinitis pigmentosa and optic atrophy.

X linked Single Gene Disorders
Duchenne Muscular Dystrophy
Becker
Haemophilia A
Fragile X

 

Duchenne muscular dystrophy

Muscular Dystrophy Campaign

Duchenne Family Support Group

Action Duchenne

Molecular scalpel hope for Duchenne muscular dystrophy – Lancet Jul 2011

http://youtu.be/6wLnR7GJakY

http://youtu.be/AZ0jQZ6aBtk

http://youtu.be/_aIAErxBskc

http://youtu.be/V4GEtfl-biE

 

Becker muscular dystrophy

Becker United Support Group

http://youtu.be/_t2-LdWJ6Y0

 

Downs trisomy 21

http://hacking-medschool.com/downs

http://www.youtube.com/watch?v=bEVkbuooXo4

http://www.youtube.com/watch?v=r7LoczaDrVE

Small stature. Brachycephalic flat expressionless face. slanted eyes with epicanthic folds. +/- convergent squint. Saffle nose prominent tongue.  Small broad hands with single palmar crease, small fingers , curved short little finger. CHD eg ASD.

Three types of Down’s syndrome
Regular trisomy 21 (94%) all the cells have an extra chromosome 21.
Translocation (4%) the extra chromosome 21 material is attached to another chromosome and one of the parents may carry the translocated chromosome without any signs of the condition themselves.
Mosaic (2%) only some of the cells have an extra chromosome 21 tends to result in milder features.

 

Fragile X syndrome

Fragile x
X linked chromosomal abnormality causing varying degress of learning disabilities
More common and more severe in males

http://youtu.be/RV3y_n5ZjFQ

http://www.youtube.com/watch?v=Symw0nU7Hys

http://www.youtube.com/watch?v=gQGtLV5uuKg

http://youtu.be/8W1f9v8Q0BY

http://youtu.be/2LD4b6sj9Jg

 

Turners syndrome

Turner Syndrome Support Society UK
Chromosome abnormality affecting only females, caused by the complete or partial deletion of the X chromosome. Commonest cause of primary ovarian failure. May also be mosaics 46 XX 47XXX.
Incidence approximately 1:2000 live female births.
Confirmation of a diagnosis of TS is by karyotype but a suspected diagnosis can be made by a series of characteristic physical features
short stature
web neck
broad chest and widely spaced nipples (shield chest)
low hairline
increased carrying angle of the elbows
short 4th metacarpal
Coarctation of aorta
etc
Two main clinical features of TS are short stature and non-functioning ovaries.
Diagnosis can be made at birth
eg newborn needs heart surgery because of coarctation of the aorta
or because of oedema of the hands and feet.
Pre-natal diagnosis is sometimes made by chorionic villous sampling, amniocentesis or ultra sound.
However, most girls are diagnosed in early childhood when growth fails or later when the absence of a pubertal growth spurt and development of secondary sexual characteristics become apparent.

http://www.youtube.com/watch?v=66jeP_JrLE0

http://youtu.be/JVq8lcCqY-A

http://youtu.be/cFvBmnhAZpQ

 

Klinefelters syndrome 47 XXY

Klinefelters Medscape

Tall stature with long legs.
Gyneacomastica
Small firm testes
Variable phenotype.
http://www.youtube.com/watch?v=QUBcDzcXRsY

http://youtu.be/DUpnEkCjBvk

 

Mitochondrial inheritance

Mitochondria contain their own set of genes (in addition to the genes in the cell’s nucleus).
Mitochondrial DNA mutations cause several well recognised disorders, often associated with neuromuscular features.
A person inherits his or her mitochondria from the egg and not the sperm.
Therefore, mitochondrial inheritance gives a pattern of the condition affecting males and females, but always inherited from a mother.
An affected male does not pass on his mitochondria to his children, so all his children will be unaffected.

http://www.youtube.com/watch?v=cR3khqNXJT8

 

Heredity Breast Ovary Bowel Ca

http://hacking-medschool.com/familial-ovarian-cancer

http://hacking-medschool.com/familial-breast-cancer

http://hacking-medschool.com/heredity-bowel-cancer

 

Genetics pedigree trees

Clinical Genetics Society 2001 Guidelines for Pedigree Drawing

Genetics Pedigree Trees @ Biotopics.co.uk

http://www.youtube.com/watch?v=9d_3-0lt17Q

http://www.youtube.com/watch?v=Ir1t9awmUl4

 

Genetic testing

UK Genetic Testing Network

http://youtu.be/cGxwsuPhDKI

http://youtu.be/1ErqwQy1Tho

http://youtu.be/snwwdepN9W4

http://youtu.be/Qo3hybgn2nU

 

Genetics counselling services

British Society of Human Genetics

http://youtu.be/Y5fb3ivxNGg

Antenatal and newborn screening

250textbooks/antenatal-timeline

NHS newborn Screening Program

Prenatal Diagnosis for Congenital Malformations and Genetic Disorders Medscape

screening.nhs.uk antenatal screening booklets

pegasus.nhs.uk

NHS Antenatal Screening Education Resources

 

Phenylketonuria PKU

What is Phenylketonuria PKU?
http://youtu.be/KUJVujhHxPQ

http://youtu.be/JVcbVLUCsqs

http://youtu.be/9zIamyWLjxM

http://youtu.be/hpaki7F4HR0

 

Hereditary amyloidosis

Hereditary amyloidosis Medline plus

Amyloid PUK

 

Contact A Family

Contact a Family

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